“Microscopic life crucial to the marine food chain is dying out. The consequences could be catastrophic.”

Scientists may have found the most devastating impact yet of human-caused global warming — a 40% decline in phytoplankton since 1950 linked to the rise in ocean sea surface temperatures. If confirmed, it may represent the single most important finding of the year in climate science.

The headlines above are from an appropriately blunt article in The Independent about the new study in Nature, “Global phytoplankton decline over the past century” (subs. req’d). Even the Wall Street Journalwarned, “Vital Marine Plants in Steep Decline.” Seth Borenstein of the AP explains, “plant plankton found in the world’s oceans are crucial to much of life on Earth. They are the foundation of the bountiful marine food web, produce half the world’s oxygen and suck up harmful carbon dioxide.”

But until now, conventional wisdom has been that big ocean impacts might not be seen until the second half of the century. This new research in Nature suggests we may have much less time to act than we thought if we want to save marine life — and ourselves. The study concludes:

In the oceans, ubiquitous microscopic phototrophs (phytoplankton) account for approximately half the production of organic matter on Earth. Analyses of satellite-derived phytoplankton concentration (available since 1979) have suggested decadal-scale fluctuations linked to climate forcing, but the length of this record is insufficient to resolve longer-term trends. Here we combine available ocean transparency measurements and in situ chlorophyll observations to estimate the time dependence of phytoplankton biomass at local, regional and global scales since 1899. We observe declines in eight out of ten ocean regions, and estimate a global rate of decline of ~1% of the global median per year. Our analyses further reveal interannual to decadal phytoplankton fluctuations superimposed on long-term trends. These fluctuations are strongly correlated with basin-scale climate indices, whereas long-term declining trends are related to increasing sea surface temperatures.

The WSJ explains, “The data are more reliable for recent decades, translating into a 40% decline since 1950.” It points out:

The team investigated several factors that could have caused the decline. “We found that temperature had the best power to explain the changes,” said Boris Worm, a marine biologist at Dalhousie and co-author of the study.

Marine algae live in the upper layers of the ocean but rely on nutrients that circulate up from lower layers. Rising temperatures mean the different layers mix less with each other, so fewer nutrients reach the algae. However, Dr. Worm noted that algal abundance can be affected by other factors, such as shifts in predator-prey populations.

Mike Behrenfeld, an expert on phytoplankton at Oregon State University, said the paper was similar to a 1992 study that used Secchi data to show a long-term decline in marine algae in the north Pacific. “But this paper covers the globe,” he said. “And the scientists also took the next step of relating the [algal decline] to sea temperatures.”

“If this holds up, something really serious is underway and has been underway for decades. I’ve been trying to think of a biological change that’s bigger than this and I can’t think of one,” said marine biologist Boris Worm of Canada’s Dalhousie University in Halifax, Nova Scotia. He said: “If real, it means that the marine ecosystem today looks very different to what it was a few decades ago and a lot of this change is happening way out in the open, blue ocean where we cannot see it. I’m concerned about this finding.”

… “Phytoplankton are a critical part of our planetary life support system. They produce half of the oxygen we breathe, draw down surface CO2 and ultimately support all of our fishes.” he said.

Certainly, scientists are going to have to verify this finding in the coming years, but as AP reports:

Previous plankton research has mostly relied on satellite data that only goes back to 1978. But Worm and colleagues used a low-tech technology “” disks devised by Vatican scientist Pietro Angelo Secchi, in the 19th century. These disks measure the murkiness of the ocean. The murkier the waters, the more plankton.

It’s a proxy the scientific community has long accepted as legitimate, said Paul Falkowski of Rutgers University, who has used Secchi disk data for his work.

He and other independent scientists said the methods and conclusions of the new study made sense.

Recognizing the importance of the article, Nature published a second piece by two leading ocean scientists, that discussed the methodology and findings, calling the work “an impressive synthesis of the relevant data”:

Taking great care, they created time series of phytoplankton biomass in the pelagic ocean, quantified as surface chlorophyll concentrations. They find a strong correspondence between this chlorophyll record and changes in both leading climate indices and ocean thermal conditions. They also show statistically significant long-term decreases in chlorophyll concentrations for eight of the ten ocean basins, and for the global aggregate.

Inaction means devastation. Resistance to a change of habits (energy) – plus how we treat the natural world (which includes us) and it’s free products is futile – because it harms “planetary boundaries” in a way which can render human presence impossible. This does include “Profits”.

Oceans hit hard human induced climate change, if this wasn’t enough we make it worse with environmental pollution.

“The Arctic Ocean has undergone some pretty big changes in recent decades,” said Kevin Arrigo of Stanford University in an interview with America.gov. He was the chief scientist aboard Healy during its mission. “Biological productivity has ratcheted up, and the timing of many key events is shifting.” That is significant, he said, because many animals key their migration to be in the Arctic when it is at its biologically most productive.

This is a 5-nail in the coffin study if it holds up. When extrapolating the timeline out from here at what point do we suffer a complete collapse of the system. Maybe 10 or 20 years? I believe people should be taking this pretty seriously.

ScienceDaily (July 29, 2010) — In an unprecedented effort that will be published online on the 28th of July by the international journal Nature, a team of scientists mapped and analyzed global biodiversity patterns for over 11,000 marine species ranging from tiny zooplankton to sharks and whales. The researchers found striking similarities among the distribution patterns, with temperature strongly linked to biodiversity for all thirteen groups studied. These results imply that future changes in ocean temperature, such as those due to climate change, may greatly affect the distribution of life in the sea.

Aside from representing the bottom few levels of a food chain that supports commercially important fisheries, plankton ecosystems play a role in the biogeochemical cycles of many important chemical elements, including the ocean’s carbon cycle.

As stated, phytoplankton fix carbon in sunlit surface waters via photosynthesis. Through (primarily) zooplankton grazing, this carbon enters the planktic foodweb, where it is either respired to provide metabolic energy, or accumulates as biomass or detritus. As organic material is typically more dense than seawater it tends to sink, and in open ocean ecosystems away from the coasts this transports carbon from surface waters to the deep. This process is known as the biological pump, and is one of the reasons that the oceans constitute the largest carbon sink on Earth. http://en.wikipedia.org/wiki/Plankton

Phytoplankton obtain energy through the process of photosynthesis and must therefore live in the well-lit surface layer (termed the euphotic zone) of an ocean, sea, lake, or other body of water. Phytoplankton account for half of all photosynthetic activity on Earth. Thus phytoplankton are responsible for much of the oxygen present in the Earth’s atmosphere – half of the total amount produced by all plant life. http://en.wikipedia.org/wiki/Phytoplankton

The number of places that peril lurks quietly and out of sight (and mind, particularly of the powerful) is astounding. It’s as though your doctor reported that nothing was really bad on your physical, just “minor” hypertension, “minor” pre-cancerous growths, “minor” lung disease, “minor” kidney malfunctions, “minor” blood sugar issues, and “minor” malnutrition.. for beginners.

In general systems fail and people die from a confluence of conditions. We’ve created a convenient shorthand for death that does not describe the avalanche of conditions that precipitate the end.

The planet is diseased from excessive fossil fuel use. Can we inhabitants survive the changes to come?

A “40% decline in the ocean’s phytoplankton speaks very strongly to James Lovelock’s Gaia Theory he describes in his latest book “The Vanishing Face of Gaia,” as attaining scientific validity and seemingly a truly powerful and very effective way to think about life on this planet.

“After much criticism, a modified Gaia hypothesis is now considered within ecological science basically consistent with the planet Earth being the ultimate object of ecological study.”

Six months ago I only had the briefest familiarity with the climate science.

Like most of those classified as “educated lay persons” I thought I had a good understanding of the science. Looking back I’ve come to realise I had – at best – a superficial understanding.

The problem I thought was longer term, perhaps a challenge for my “grandchildren”.

However early this year I decided to take the deep plunge and immerse myself in both the popular and scientific literature on AGW. I also explored the claims of the “denial machine” in depth. In the end I began blogging about the deniers in order to help expose the level of their deceit.

Six months later I’m still a novice: however I’m far more familiar with the basic science and its worrisome implications.

But this… Christ.

This is the most *terrifying* thing I’ve read all year.

I can understand the basic human need to deny bad news. I understand the psychology that fuels the denial machine. I can now fully appreciate the almost pathological need to deny AGW.

So it’s taken most of two decades for research to be funded to discover that the decline of plankton in the north Pacific was not a regional anomaly, but one facet of a cumulative global phenomenon.

The present news is appalling in at least two ways –
it compounds the threat to all marine life posed by acidification, as well as to the terrestrial biodiversity dependent on it –
and it is also reports a major new carbon feedback, since the loss of the plankton-shell carbon sink would raise by around half the amount of our annual anthro-CO2 output that remains in the atmosphere.

Thus we face accelerated losses of both food and climate security from this one phenomena. Those nations whose historical GHG emissions have caused this damaging warming impact on the oceans’ productivity need to start acknowledging their liabilities without further prevarication.

Better news is that many American’s I’ve known seem to share a concern over the supply of oxygen in the atmosphere – which is one fear I’d not now assuage. So maybe this news will turn some heads ? (Note unusual WSJ interest).

It is also relatively good news that the plankton decline is primarily warming driven, as opposed to acidity or airborne carbon concentration being the main driver, as the latter issues are far less open to prompt mitigation.

In this context it appears that while geoengineering [Geo-E] in the form of carbon recovery is very urgently required as a means of cutting airborne carbon and thereby, not least, of controlling marine acidification,
it is equally plain that albido restoration is essential, and urgent, not least as a means of halting the warming that drives plankton’s decline.

To pre-empt any kneejerk reactions I’d add that there is simply no point in attempting Geo-E without committing to a radical global program to end GHG outputs, and that the first step for effective Geo-E implementation is the agreement of global governance over its research, development and deployment.

That said, can anyone reading this identify a means of cutting airborne carbon and limiting global temperature swiftly enough to save the oceans that does not demand Geo-E ?

If not, hadn’t we better start discussing the ways and means of Geo-E, rather than just bypassing the subject ?

Meaning that we need a far wider debate ASAP on the means of doing Geo-E prudently and competently to be prepared for that u-turn,
and we need also to prepare the position that no sane government should accede to a global Geo-E program without exacting an appropriate price in return –
in short, ratification of a “Treaty of the Atmospheric Commons.”

@Lewis #22: You’re right, it’s good news that it’s primarily warming. Even better is, it’s mediated by reduced nutrients because of less surface/deep mixing. That does open up the possibility of geoengineering in several ways. You can cool the planet (artificial volcanoes), or you can directly mix the oceans (???).

Of course, I agree that Geo-E is a last resort and at best a lesser evil. The good thing is that I think human nature is on our side in that debate, at least. The global public will not stand for massive, expensive, side-effect-ridden programs unless it’s clear that the alternative is worse.

“plant plankton found in the world’s oceans.. produce half the world’s oxygen and suck up harmful carbon dioxide.”

We discuss CO2 and methane a lot. Does the statement above mean climate change will also cause a decline in atmospheric oxygen concentration? Is climate change going to literally suffocate humanity to death?

I was reading about this in another blog, at Sc Am, and someone complained that they could not read the original Nature article because it required a subscription. For those of you in the U.S. who are not professors or scientists there is a way to get access. At any public university in your state you can buy a library membership. You should be given an access code and then you’ll be able to read anything their library has online access to.

Isn’t this an accurate parallel to the PT mass extinction? That was my immediate suspicion, and the article Prokaryotes linked to in post no. 19 asserts the same. I’d love to hear from a few climatologists and others “in the biz” on that. Hydrogen sulfide instead of oxygen? 70-90% die-off? 2048?!

Preferably, I would really, really like them to say “no, it may be bad but not that bad.” Yeah, I’d really like that.

“… think human nature is on our side in that debate, at least. The global public will not stand for massive, expensive, side-effect-ridden programs unless it’s clear that the alternative is worse.”

I tend to believe opposite: having ignored, denied and delayed the issue for decades there will be panic when AGW hits hard.

Historically we’ve acted in the short term, how is that going to change?

Given current trajectories, I think most readers here would agree that food security may very well be an issue.

People in the developed world they will experience something they haven’t experienced for nearly 200 years: an insecure food supply. Without doubt we are going to see collapsing fish stocks and grain shortages as more intense droughts seriously disrupt the global food chain.

After decades of literally gorging themselves on cheap sugars and carbs to the point that obesity is genuine health issue, people in the “West” will be shocked to discover our food supply network is built upon some shaky foundations (and far more dependent on natural systems than they’d ever realised).

This will induce genuine *fear*.

Think how people reacted in Ireland in during 19th century during the potato famine (they fled). Think Germany in WW1 during the Turnip Winter and during the post-war blockade that caused starvation (this experience helped turn them towards extreme left and right wing politics and increased post-war bitterness). Think Leningrad in 1942 or the Ukraine during the 1930s (things got real ugly). I cite these examples because the provide a good template for what happens to previously affluent, modern societies experiencing serious stress due to food insecurity.

I may sound deeply pessimistic, however history is very illustrative when it comes to human nature.

The general public barely understands the science of climate change. How will they cope with further debate on Geo-E?

A recent study by Cardiff Uni on public perception of climate change and energy issues is illustrative. Firslty it notes delcine in the “belief” in AGW.

Many here have no doubt seen the report, as it was covered by many climate blogs. However for me there was an even more interesting serious of questions posed to survey respondents: what did they know about Geo-E and would they support its use.

Here is what the report said:

“….Three-quarters (75%) of respondents had either not heard of geoengineering or knew ‘almost nothing about it’. Only 7% of respondents “knew a fair amount’ or more about geoengineering.”

No surprises there.

But here is the kicker:

“…Nevertheless, nearly half (47%) of respondents would tend to strongly support geoengineering approaches to tackling climate change in
principle, with only 4% tending to oppose or strongly opposing. However
50% of respondents were either unsure (i.e. stated ‘neither support or
oppose’) or did not have an opinion on the issue.”

Despite never hearing about Geo-E before, nearly half supported it.

This tends to make me think it will drive people to look for the quickest and (perceived) easiest solution.

“Isn’t this an accurate parallel to the PT mass extinction? That was my immediate suspicion, and the article Prokaryotes linked to in post no.”

Yes – ocean acidification and methane deposits which bubble up from the ocean sediment are linked – we can observe such effect currently in the Gulf on a smaller scale. Once the northern ice shield is gone we will see things progress much faster, from the extra energy input and ecological collapse. And partly these processes are irreversible once started – i.e. massive methane during PETM “Clathrate Gun”. The only Geo-E mechanisms which seem viable are “natural of nature” – to sequester carbon with biochar on large scale, create carbon sinks, plant trees and preserve carbon sinks.

Biochar brought into soils, helps against the drought, flood erosion, creates higher crop yields – with less petrol fertilizer, and removes greenhouse gasses from the carbon cycle, if stored into the soil. An alternative to slash and burn.

This is the base for civilization sustainability. A failed state cannot help curb emissions and biochar adopting nations could get technology in return and are emerging clean economies/markets. Biochar helps “us” to lower the dangerous amount of Co2 in the atmosphere. Dr. Lovelock calculated, that if all farmers worldwide adopt biochar we can have an impact with slowing climate change and maybe reverse it. Of course all these technologies to engineer earth soils make only sense if we reduce emissions. It is not to late yet, but we are about to see that change as climate change becomes more pronounced and persistent – manifest.

Solutions and it success have a lot to do with worldwide teaming, trust & unity.

if you read the paper, the “2048” comment came as sort of an afterthought. It was a paper on marine diversity, and the 2048 “projection” was a simple literal extrapolation from global catch data. The “If” statement by Worm is couched with caveats, but the media propagated his results as if it was a precise estimate. Of course he was bashed hard by other scientists (Hilborn) for his methodology, but it was probably due in part to the undue media exposure of the 2048 figure. I guess I’m trying to say that Worm is still a foremost expert on marine biodiversity.

Though there are other viable hydrospheric engineering mechanism “Hydro-E” for that matter, which could be adopted. Like creating corals and preserve them, pumping oxygen into the ocean or plant specific algae, to fight ocean anoxia – oxygen depletion and ocean acidification.

I’m sure there are some competent biologists out there that could answer your question, but I’d suggest the time scale for evolutionary processes is relatively slow.

Climate change may be happening too fast for new varieties to evolve – species extinction is already happening.

I suspect that new varieties or species will evolve to adapt to the changed conditions. However species not suitably adapted will die off.

Hope lies in cutting CO2 emissions and investing in infrastructure robust enough for life on a changed planet. Cap and trade, direct taxation of CO2, solar, nuclear… what ever. We need to stop pumping CO2 into the atmosphere now.

I also have a daughter, and yes it concerns me. Which is why I’m working damn hard to make a difference.

No need to wait for loss of Arctic ice cap in 3 to 6 years, this is one of the “Pearl Harbor” events that should be driving us to immediately develop and move to transportation and systems 1% and less than transportation systems based on cars; and other extremely critical efforts.

“Triage the population.” The likelihood of that happening in our lifetime was brought up by Professor Peter Ward the other night during a special radio interview on pollution and climate change with Art Bell (“The Day After Tomorrow”). Judging from the phone calls aired during the program, Ward’s ninth-inning, workingman talk about dying oceans alone left a lot of badly shaken skeptics out there. Bell knew the skeptics were organized and waiting to flood the show with propaganda, and he trumped them by allowing only skeptics to phone in questions for much of the three-hour program. Bear in mind this was a special appearance by Bell. The regular host is, well, a dim bulb who appeals to skeptics and serves as a major propaganda pipeline for Big Oil and big polluters. As a result, they threw every angle and tactic at Ward, who probably broke some kind of homerun record. The skeptics became so unwound they were reduced to calling Ward and Bell “Communists” of all things. Ward and Bell were, by the way, very civil and patient, especially under the circumstances, and provided a historic teaching moment in radio. By show’s end Bell was having to repeatedly ask for skeptics to call in their questions because Ward had answered them all pretty early on. Congratulations to Professor Ward and Art Bell for bringing the world a few hours of enlightenment in the dead of night.

From what I’ve read it’s not the case that higher sea temperatures are killing plankton but rather that their food source is out of reach as the composition of the ocean changes. As the Independent newspaper puts it:

One effect of rising sea temperatures has been to make the water column of some regions nearer the equator more stratified, with warmer water sitting on colder layers of water, making it more difficult for nutrients to reach the phytoplankton at the sea surface.

This is not something which plankton will be able to adjust to so easily unfortunately.

This change in ocean plankton is of great concern. However, some of the verbaige here is not accurate. It’s not really a case of phytoplankton dying–rather production (growth) is being reduced due to declining nutrients, mainly nitrogen. This is due to the well known case of higher temperature leading to less vertical mixing of the water column. There is also no concern about the earth’s O2 supply, although the ability of the oceans to act as a CO2 sink could certainly decline. This kind of a change in productivity is well documented in Lake Tanganyika, one of the world’s biggest deep lakes. There climate warming has also lead to lower plankton producitivity. There’s a good article (open access) in the December 2009 special issue of Limnology and Oceanography available at the ASLO.org web site on Lake Tanganyika.

Take a look around you, Climate Progress readers. It is obvious if you just look that the trees have been in die-back for decades. Some of it is simply from a warmer climate with more sporadic precipitation. Most of it is toxins from fuel emissions – particularly ozone.

The inexorably rising level of tropospheric ozone all around the globe is causing crop failures in epic proportions, RIGHT NOW. Ozone makes plants more susceptible damage from to fungus, disease, and insects, as well as drought and wind.

I’m not making this up! It’s been thoroughly researched and published by scientists. But nobody wants to pay attention to it, any more than they want to pay attention to the depleted fish stocks in the oceans, the decline in phytoplankton, the acidification of the water, or the sources of cancer.

Use of fuel should be rationed and restricted to only the most essential uses while we transition to clean energy. This is an emergency (!) because aside from all the terrible impacts of changing the climate, we are poisoning the bottom of the food chain AND the source of oxygen.

The stratification of the oceans is exactly what was predicted by James Lovelock as a result of global warming. If I remember correctly his main point was that deeper layers would become deoxygenated, and that would kill off most of the aerobic life. What would the world be like if most of the volume of the oceans became only habitable by anaerobic life?

“The only Geo-E mechanisms which seem viable are “natural of nature” – to sequester carbon with biochar on large scale, create carbon sinks, plant trees and preserve carbon sinks.”

As you know I’m a staunch supporter of the Biochar option, not least for its potential to incentivise global afforestation with associated biodiversity gains.
But, with respect, in view of the various threatening rates of change now reported, the assumption that Carbon Recovery Geo-E could by itself be sufficiently swift to avoid the destruction of ocean biomass by warming and acidification, and to avoid the interactive feedback loops running amok, seems to me like wishful thinking.

To test this as best I can, I ran a spread with a range of time/data series, some of which are necessarily notional, with CO2 ppmv as the metric.
The following values are ascribed:

In 2040, airborne CO2 is at 426ppmv without Biochar, and 340ppmv with its radical deployment. Allowing for the ~35-yr timelag on GHGs’ warming impact after their release, the ‘active’ ppmv rises from the present 330ppmv to reach 381ppmv in 2040, and 391ppmv in 2045.

In 2050, airborne CO2 is at 438ppmv without Biochar, and 309ppmv with its radical deployment. Allowing for the ~35-yr timelag on GHGs’ warming impact, with early Biochar gains starting to take effect, the ‘active’ ppmv reaches 397ppmv in 2050, and a peak of just over 398ppmv in 2052. After this it begins to decline, returning to 390ppmv in 2060.

This rather simplistic scenario includes both very radical rates of GHG cuts and of Biochar deployment, with arguably modest projections of sink decline and feedback acceleration.
Yet it indicates that with all these factors the ‘active’ ppmv, whose warming impact drives all of the sundry threats, reaches a peak of 398ppmv in 2052, which is 68ppmv higher than the present 330ppmv.
This seems to me utterly untenable as a planned target.

Therefore I’d hope that, with further consideration, we may some day agree that the most cautious effective means of Albido Enhancement is pre-requisite to halting the warming ASAP, thereby controlling both the feedbacks’ outputs and the sinks’ decline and so transforming our prospects.

By the way, Soylent Green won’t work. There’s the nasty problem of prions which if we actually made soylent green would cause the human form of mad cow disease to spread throughout the population. Cannibalism can’t be a part of any human nutrition solution for biological reasons, never mind the ethical ones.

————————————–
In the period from mid-2001 until mid-2005, we see an average increase of CO2 in the atmosphere of (1.7±0.2) ppm y−1, and a corresponding decrease of the airborne O2 fraction of (−20±2) per meg y−1, mainly caused by human activities, particularly fossil fuel burning. The major feature in the records is the fast decrease of the airborne O2. This decrease must be caused by an O2 sink up to now not accounted for. Two mechanisms have recently been proposed in the literature (Ciais et al., 2007; Randerson et al., 2006). An O2 decrease acceleration seems to have started during or shortly after the anomalously hot and dry summer in Europe of 2003. A relation between both is, however, still speculative, and the statistical base and significance are still small.
————————————–

Time for some engineers to brainstorm the cheapest way to vertically mix the water on an oceanic scale. It’s win/win – more O2 and CO2 down deep where pressure increases solubility and where deep fish can grow, more nutrients and cold (thus better O2 and CO2 solubility) at the top.

Idea number 1: it’s those damn rivers, dumping fresh water onto the top layer. Pipe the fresh water into somewhere deep and nutrient rich, and ensure that it mixes well before the low salt makes it float up. It would locally screw up delta ecosystems… well, I was going to make a sardonic comment about the Mississippi, but I just looked it up, and the Amazon has almost 5 times more flow than the next biggest. You could pipe a Mississippi worth out of the Amazon, and the delta would hardly notice.

Those fresh waters are rich in nutrients and dissolved organic carbon–You don’t really want that freshwater forced down deep. I have read about mixing systems for the Gulf to reduce the risk of strong hurricanes from high surface temperatues. You would need 10’s of thousands of wind or wave powered mixing divices just for the gulf of mexico. Probably not a feasible investment for large parts of the open oceans.

The problem is that the mass of water increase per degree temp increase is much higher for warmer water. The amount of work done by wind to mix a stratified water column is enormous, especially at higher temperatures.

Mae-Wan Ho of the Institute of Science in Society (article link see #46) is focussing on O2 decrease too. Her hypothesis is that there’s a link with deforestation on behalf of biofuel agriculture. For now, this seems highly speculative to me.

I think it’s likely that the methane hydrates are dissociating, and that is one thing driving the acidification.

Ecosystems often fail because keystone species are removed, so I read. Most keystone species are predators, sometimes the top predator in the food chain. Tuna and other commercial fishing comes to mind, as possible causes of this decline in plankton, as does the use of commercial fertilizers and phosphate containing detergents.

Whatever the cause, oceanic anoxic events have been associated with many past mass extinctions. Google “oceanic anoxic event” on Wikipedia, and this will pop right up.

Oceanic anoxic events or anoxic events occur when the Earth’s oceans become completely depleted of oxygen (O2) below the surface levels. Although anoxic events have not happened for millions of years, the geological record shows that they happened many times in the past. Anoxic events may have caused mass extinctions. These mass extinctions were so characteristic they include some of those which geobiologists employ to serve as a time marker in biostratigraphic dating. It is believed oceanic anoxic events are strongly linked to lapses in key oceanic current circulations, to climate warming and greenhouse gases.

Analysis of the geologic records occurring before and after the affected ages are that onsets are rapid and so are recoveries. Both sets of data suggests that a sudden climate threshold or tipping point occurs at about four times the Earth’s mean carbon dioxide levels relative to the baseline concentrations of about 280 ppmv in circa 1750. This date is significant in that it is regarded as the beginning of the Industrial age. Strata analysis suggests that in the era when Earth had a predominantly overheated climate,[1] with heavy daily rains and violent storms,[2] the relatively fierce global climate resulted in far heavier erosion which in turn fed more nutrients into the world’s waters. At the same time it caused deep water circulation between the poles and the equator to stop in a cataclysmic fashion.[3] This obstruction in oceanic circulation led to ‘death in the depths’ from oxygen deprivation. The stagnation caused by this lack of circulation could not be offset by natural processes and became a source of mildly poisonous hydrogen sulfides. The stratified waters would support life in the oxygenated surface layer but the deeper layers became a lethal mixture where life was impossible. The toxic lower layers halted scavenger activity along the organically rich ooze, or sapropel, and all creatures that died in it drifted down and accumulated on the abyssal basins and bottoms. All these life forms unwarily drifting into the anoxic or toxic layers would have died and contributed to the continual accumulation of unicellular microorganisms. The surface layer benefited from an explosion in life, spurred by the increased nutrients from the super-greenhouse conditions, which was then killing itself in waste products.[citation needed] Ironically these deposits of sedimentary organic materials may have accumulated into lipid rich deposits. It is now widely believed that most of today’s fossil oil reserves formed in several distinct anoxic events in earth’s geologic history.

We’re on track to see 1100 ppm of CO2 by the end of the century, I guess, if this speculation about an oceanic anoxic tipping point at four times our baseline CO2 level is correct. Of course, the rapidity and the variety of the changes we are imposing could bring the tipping points to fruition sooner, possibly.

Our impact on the oceans might be kind of like noise in the system. By fishing the top predators, adding nutrients along the coasts, and adding CO2 to the atmosphere, we may be interfering with natural feedback loops that keep the oceans in dynamic equilibrium.

I haven’t really thought this through, but I am wondering whether this has any implications regarding the “missing carbon”? I.e. we roughly know what our emissions are, and we can measure the increase in the atmosphere and ocean, and the working assumption is that the difference is accounted for in the land systems – but where exactly is uncertain (longer growing seasons? etc.?).

Like I said, it’s just idle musing on my part. It would have to entail some sort of deep ocean sequestration of carbon, and I am not sure what mechanism would drive this on a large scale, but I’m just wondering out loud. At most it would be just part of the carbon accounting puzzle.

I’m still learning about this, but it seems of concern in the event of huge amounts of hydrocarbons “methane” released into the ocean and atmosphere. When hydrocarbons break up in the atmosphere oxygen is lost. Aquatic dead zones can result from different causes/sources and are an example of oxygen depletion in the ocean.

Certainly more recently they have – i.e. when we have been directly measuring this, ~ 1989. It is documented in the IPCC WG1 and SPM FAQ, if I recall correctly. Interestingly, the leading researcher on this is Ralph Keeling, son of the man for whom the Keeling Curve for atmospheric CO2 is eponymously named.

And this is another fingerprint for the rise in CO2 concentrations being due to our emissions. Combusting hydrocarbons consumes O2. It’s all tied together.

Oops. I converted 2 x 10^-4 to 1/2000 instead of 1/5000. Thanks for the correction. In any case, the thrust of the comment was to head off the anticipated argument that a dramatic decrease in phytoplankton population should result in an immediate dramatic decrease in atmospheric oxygen which would therefore invalidate the phytoplankton study.

The yearly decrease is approx. 0.0003% in the overall concentration of oxygen in the atmosphere.

So if this decline would persist, an unhealthy level of O2 were to be reached in about (21 – 19,5)/0.0003 = 5000 years. That would probably require massive amounts of fossil fuels being burned during all this time – thankfully there isn’t enough of the stuff left.

Then again…

1/6000 02 addition per year is 0,0167%.

If de decline in phytopankton would accelerate, so that, for example, in 2050 only half of the present amount would be left, and if at present phytoplankton is contributing 1/12000 (dixit Worm a.o), due to phytoplankton decline alone the yearly addition would decline by 1/24000.

Then – since we are losing 02 (slowly) already – by 2050 we would yearly have a decline of more than 1/12000 of the total amount of O2, i.e. about 0.008%.

Well, 1.5% / 0.008% = appr. 200 years left before breaking the OSHA health norm – presupposing also that until 2250 we keep burning coal and oil at appr. the present speed – which probably (thank God) isn’t possible because of shrinking availability.

Of course this is only a purely speculative very bad case scenario. And I’m just improvising and probably making some serious errors? Anyone?
[ Note to Joe Romm: feel free to remove this comment if it doesn’t make sense enough!]

But to my mind, this little exercise does present another reason not to keep gambling by continuing to burn fossil fuels; in other words, perhaps Dr. Mae-Wan Ho has a case here, were she reponds to the comment that there is no cause for concern given the vast amount of O2 and the slow decline rate at present: ‘O2 is there principally because of carbon storage time, its rate of drop currently is ~10 ppm, but it could well swing further downwards’.

By the way, Prokaryotes, Mae-Wan Ho is opposing Biochar in the light of O2-decline – and of course, this is hotly debated (see beneath the article) too.

If the title does not sound right, remember that; “Erba et al. studied the numbers and condition of fossilized specimens of calcareous nannoplankton, the microscopic ancestors of modern plankton.”

What was most interesting to me is; “It has long been known from the fossil record that various species of land animals shrank in size during the PETM. For animals this makes thermodynamic sense—the ratio of surface area to volume is higher for small animals than for large ones. This means a small animal can shed excess heat more readily than a large animal. For the marine creatures, the size change is seen as a response to dropping oxygen and carbonate levels.”

Uhm, i think there is some lack of method analysis. And the way she oposes IBI seems a little over the top – ofc people want this introduced in climate legislation. We need this for large scale action.

Dr. Mae-Wan Ho “Turning trees into charcoal in a hurry could be the surest way to precipitate an oxygen crisis from which we may never recover.”

Nobody suggest to chop of our forest – see Slash and Burn from mainstream farmer practise and a more potent biofuel source.
The main idea is to use scrap organic material – such as organic household waste – stuff which decomposes anyway.

Dr. Mae-Wan Ho “These findings show that BC is a substantial oxygen sink, and could deplete atmospheric O2 fairly rapidly if massive amounts are produced in a hurry!”

The plants which grow on soils prepared with biochar offset the oxygen uptake from soils

Dr. Mae-Wan Ho “Biochar effects on soil fertility not always positive.”
True, and this is why you need to assess soil chemistry “PH” before you apply biochar. And ofc the product could and should be optimized with synergetic reactions “amendments”.http://www.i-sis.org.uk/bewareTheBiocharInitiative.php

That scale is not measured in calendar years, but in the respective organisms’s generational spans. Evolution can readily/visibly occur in as little as 100 generations; but how much time that amounts to will depend on the organism. Thus, we witness the substantial evolution of various bacteria in just two or three human generations.

While it is certainly no excuse to be sanguine, there is reason to suppose that phytoplankton might have a shot at adaptation in the short term that longer generational organisms would lack.

One error (slip of the pen) over there is, of course, ‘oxidation of CO2′.

Please read that paragraph as ‘increase of O2-lost-in-O2-sinks (such as oxidation of methane and forest fires) by 1/24000 of present total amount of 02′. Whether that – or an even worse increase of O2 loss – is a realistic possibility, I don’t know.

You are much too pesimistic. There are many published experimental studies of rapid evolution in bacteria and algae. (try google sholar searches under “rapid evolution in plankton” for example). Evolution in bacteria can take place in hours and in algae significant evolution occurs in days. However, there are basic stoichiometric constraints. By this I mean, organisms cannot evolve to grow without sources of carbon, nitrogen and phosphorus. The limiting nutrient for phytoplankton in oceans is usually nitrogen and an organism can’t make protein without N. The amount of N will affect which species are most successful, but a lack of N will lead to low abundance and production of phytoplankton. The basic problem of low N caused by less mixing in the water column may result in species and genotypes with more efficient N use, but evolution cannot solve the basic problem.

about getting access to subscription only publications such as Nature by joining your local public university library. What I wanted was full remote access from my home computer to whatever the University of Washington pays subscriptions for that is online, and so far, I can’t get it.

UW, for instance, does not allow members of the public to get full access to their library system by paying a fee. You can visit the library and read anything on their shelves, use a computer there to access some of what a student or other person with full access has access to, but you can’t just pay and get access to whatever you want. There are loopholes, such as if you are over 60 yrs old and can take one “Access” program course, or if you sign up for “Educational Outreach” courses, but so far I’ve not found a way to get in.

On the general topic of will warming cause a general decline in the Earth’s capacity to support life: this Nature report isn’t conclusive.

Obviously, because, to use Hansen’s words, the “hammer blow” to the climate system of fossil fuel caused CO2 injection into the atmosphere is occuring in a geological instant (i.e. a few hundred years), there may well be geologically brief periods (centuries or millenia) where less life actually exists, unless Hansen’s Venus Syndrome prediction, where Earth’s oceans boil away, proceeds. Otherwise, ecological “niches” opened up by the mass extinction event will be a grand opportunity for new life forms which will evolve to fit.

Why in millions of years, Earth will be looking good, strutting around the solar system on Friday nights looking for action.

Humans seem headed to be a tiny remnant of this civilization – perhaps living in climate controlled dome covered cities on a hostile planet – or to extinction.

“The Climate War”, by Eric Pooley, features Bill Clinton’s review on the back cover. An excerpt: “This story has heroes, like my friend Al Gore, and it has some villains. What it doesn’t have is an ending; that part is still up to us…..”

Kind of like humanity is looking to the cosmos to protect civilization from a meteor strike in five hundred years and in reality humanities’ life style could well destroy the prospects for future life in as little as 4 years.

Here’s a simple prescription: step down in the food chain and stop consuming animals, birds, fishes and their by-products (skin, milk, etc.) and allow Nature to recover. This is a lot quicker and simpler than expecting fossil fuel usage to disappear overnight or geo-engineering the churning of the oceans.

Sorry that did not work out for you. Maybe you can make an occasional trip to their library. How far away is it? You might even check with you public library or community colleges. Nature is very expensive, but they might have access to some science journals.

The U. of Cal. is in a major battle with Nature Publishing Group over the high price: “The University of California system has said ‘enough’ to the Nature Publishing Group, one of the leading commercial scientific publishers, over a big proposed jump in the cost of the group’s journals.”

I think there needs to be a good narrative around this study. If you read about the previous work on ocean phytoplankton you’ll see two things: increasing but sparse evidence of a decline and the great difficulty in determining the big picture over time. The idea of using Secchi disk data is very eloquent, simple yet painstakingly tedious. Someone should do a write up – just an essay for now – along the lines of Wearts’ “Discovery of Global Warming” but with elements of Sobel’s wonderful book “Longitude.”

I don’t mean to imply that the plankton decline is “settled science”; it does need further corroboration and we need a much better understanding of the implications. But there is a great story in this that needs to be told.